1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * net/core/fib_rules.c Generic Routing Rules
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 */
7
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/list.h>
12 #include <linux/module.h>
13 #include <net/net_namespace.h>
14 #include <net/inet_dscp.h>
15 #include <net/sock.h>
16 #include <net/fib_rules.h>
17 #include <net/ip_tunnels.h>
18 #include <linux/indirect_call_wrapper.h>
19
20 #if defined(CONFIG_IPV6) && defined(CONFIG_IPV6_MULTIPLE_TABLES)
21 #ifdef CONFIG_IP_MULTIPLE_TABLES
22 #define INDIRECT_CALL_MT(f, f2, f1, ...) \
23 INDIRECT_CALL_INET(f, f2, f1, __VA_ARGS__)
24 #else
25 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
26 #endif
27 #elif defined(CONFIG_IP_MULTIPLE_TABLES)
28 #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__)
29 #else
30 #define INDIRECT_CALL_MT(f, f2, f1, ...) f(__VA_ARGS__)
31 #endif
32
33 static const struct fib_kuid_range fib_kuid_range_unset = {
34 KUIDT_INIT(0),
35 KUIDT_INIT(~0),
36 };
37
fib_rule_matchall(const struct fib_rule * rule)38 bool fib_rule_matchall(const struct fib_rule *rule)
39 {
40 if (READ_ONCE(rule->iifindex) || READ_ONCE(rule->oifindex) ||
41 rule->mark || rule->tun_id || rule->flags)
42 return false;
43 if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1)
44 return false;
45 if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) ||
46 !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end))
47 return false;
48 if (fib_rule_port_range_set(&rule->sport_range))
49 return false;
50 if (fib_rule_port_range_set(&rule->dport_range))
51 return false;
52 return true;
53 }
54 EXPORT_SYMBOL_GPL(fib_rule_matchall);
55
fib_default_rule_add(struct fib_rules_ops * ops,u32 pref,u32 table)56 int fib_default_rule_add(struct fib_rules_ops *ops,
57 u32 pref, u32 table)
58 {
59 struct fib_rule *r;
60
61 r = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
62 if (r == NULL)
63 return -ENOMEM;
64
65 refcount_set(&r->refcnt, 1);
66 r->action = FR_ACT_TO_TBL;
67 r->pref = pref;
68 r->table = table;
69 r->proto = RTPROT_KERNEL;
70 r->fr_net = ops->fro_net;
71 r->uid_range = fib_kuid_range_unset;
72
73 r->suppress_prefixlen = -1;
74 r->suppress_ifgroup = -1;
75
76 /* The lock is not required here, the list in unreachable
77 * at the moment this function is called */
78 list_add_tail(&r->list, &ops->rules_list);
79 return 0;
80 }
81 EXPORT_SYMBOL(fib_default_rule_add);
82
fib_default_rule_pref(struct fib_rules_ops * ops)83 static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
84 {
85 struct list_head *pos;
86 struct fib_rule *rule;
87
88 if (!list_empty(&ops->rules_list)) {
89 pos = ops->rules_list.next;
90 if (pos->next != &ops->rules_list) {
91 rule = list_entry(pos->next, struct fib_rule, list);
92 if (rule->pref)
93 return rule->pref - 1;
94 }
95 }
96
97 return 0;
98 }
99
100 static void notify_rule_change(int event, struct fib_rule *rule,
101 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
102 u32 pid);
103
lookup_rules_ops(const struct net * net,int family)104 static struct fib_rules_ops *lookup_rules_ops(const struct net *net,
105 int family)
106 {
107 struct fib_rules_ops *ops;
108
109 rcu_read_lock();
110 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
111 if (ops->family == family) {
112 if (!try_module_get(ops->owner))
113 ops = NULL;
114 rcu_read_unlock();
115 return ops;
116 }
117 }
118 rcu_read_unlock();
119
120 return NULL;
121 }
122
rules_ops_put(struct fib_rules_ops * ops)123 static void rules_ops_put(struct fib_rules_ops *ops)
124 {
125 if (ops)
126 module_put(ops->owner);
127 }
128
flush_route_cache(struct fib_rules_ops * ops)129 static void flush_route_cache(struct fib_rules_ops *ops)
130 {
131 if (ops->flush_cache)
132 ops->flush_cache(ops);
133 }
134
__fib_rules_register(struct fib_rules_ops * ops)135 static int __fib_rules_register(struct fib_rules_ops *ops)
136 {
137 int err = -EEXIST;
138 struct fib_rules_ops *o;
139 struct net *net;
140
141 net = ops->fro_net;
142
143 if (ops->rule_size < sizeof(struct fib_rule))
144 return -EINVAL;
145
146 if (ops->match == NULL || ops->configure == NULL ||
147 ops->compare == NULL || ops->fill == NULL ||
148 ops->action == NULL)
149 return -EINVAL;
150
151 spin_lock(&net->rules_mod_lock);
152 list_for_each_entry(o, &net->rules_ops, list)
153 if (ops->family == o->family)
154 goto errout;
155
156 list_add_tail_rcu(&ops->list, &net->rules_ops);
157 err = 0;
158 errout:
159 spin_unlock(&net->rules_mod_lock);
160
161 return err;
162 }
163
164 struct fib_rules_ops *
fib_rules_register(const struct fib_rules_ops * tmpl,struct net * net)165 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
166 {
167 struct fib_rules_ops *ops;
168 int err;
169
170 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
171 if (ops == NULL)
172 return ERR_PTR(-ENOMEM);
173
174 INIT_LIST_HEAD(&ops->rules_list);
175 ops->fro_net = net;
176
177 err = __fib_rules_register(ops);
178 if (err) {
179 kfree(ops);
180 ops = ERR_PTR(err);
181 }
182
183 return ops;
184 }
185 EXPORT_SYMBOL_GPL(fib_rules_register);
186
fib_rules_cleanup_ops(struct fib_rules_ops * ops)187 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
188 {
189 struct fib_rule *rule, *tmp;
190
191 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
192 list_del_rcu(&rule->list);
193 if (ops->delete)
194 ops->delete(rule);
195 fib_rule_put(rule);
196 }
197 }
198
fib_rules_unregister(struct fib_rules_ops * ops)199 void fib_rules_unregister(struct fib_rules_ops *ops)
200 {
201 struct net *net = ops->fro_net;
202
203 spin_lock(&net->rules_mod_lock);
204 list_del_rcu(&ops->list);
205 spin_unlock(&net->rules_mod_lock);
206
207 fib_rules_cleanup_ops(ops);
208 kfree_rcu(ops, rcu);
209 }
210 EXPORT_SYMBOL_GPL(fib_rules_unregister);
211
uid_range_set(struct fib_kuid_range * range)212 static int uid_range_set(struct fib_kuid_range *range)
213 {
214 return uid_valid(range->start) && uid_valid(range->end);
215 }
216
nla_get_kuid_range(struct nlattr ** tb)217 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
218 {
219 struct fib_rule_uid_range *in;
220 struct fib_kuid_range out;
221
222 in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]);
223
224 out.start = make_kuid(current_user_ns(), in->start);
225 out.end = make_kuid(current_user_ns(), in->end);
226
227 return out;
228 }
229
nla_put_uid_range(struct sk_buff * skb,struct fib_kuid_range * range)230 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
231 {
232 struct fib_rule_uid_range out = {
233 from_kuid_munged(current_user_ns(), range->start),
234 from_kuid_munged(current_user_ns(), range->end)
235 };
236
237 return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out);
238 }
239
nla_get_port_range(struct nlattr * pattr,struct fib_rule_port_range * port_range)240 static int nla_get_port_range(struct nlattr *pattr,
241 struct fib_rule_port_range *port_range)
242 {
243 const struct fib_rule_port_range *pr = nla_data(pattr);
244
245 if (!fib_rule_port_range_valid(pr))
246 return -EINVAL;
247
248 port_range->start = pr->start;
249 port_range->end = pr->end;
250
251 return 0;
252 }
253
nla_put_port_range(struct sk_buff * skb,int attrtype,struct fib_rule_port_range * range)254 static int nla_put_port_range(struct sk_buff *skb, int attrtype,
255 struct fib_rule_port_range *range)
256 {
257 return nla_put(skb, attrtype, sizeof(*range), range);
258 }
259
fib_rule_match(struct fib_rule * rule,struct fib_rules_ops * ops,struct flowi * fl,int flags,struct fib_lookup_arg * arg)260 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
261 struct flowi *fl, int flags,
262 struct fib_lookup_arg *arg)
263 {
264 int iifindex, oifindex, ret = 0;
265
266 iifindex = READ_ONCE(rule->iifindex);
267 if (iifindex && (iifindex != fl->flowi_iif))
268 goto out;
269
270 oifindex = READ_ONCE(rule->oifindex);
271 if (oifindex && (oifindex != fl->flowi_oif))
272 goto out;
273
274 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
275 goto out;
276
277 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
278 goto out;
279
280 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
281 goto out;
282
283 if (uid_lt(fl->flowi_uid, rule->uid_range.start) ||
284 uid_gt(fl->flowi_uid, rule->uid_range.end))
285 goto out;
286
287 ret = INDIRECT_CALL_MT(ops->match,
288 fib6_rule_match,
289 fib4_rule_match,
290 rule, fl, flags);
291 out:
292 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
293 }
294
fib_rules_lookup(struct fib_rules_ops * ops,struct flowi * fl,int flags,struct fib_lookup_arg * arg)295 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
296 int flags, struct fib_lookup_arg *arg)
297 {
298 struct fib_rule *rule;
299 int err;
300
301 rcu_read_lock();
302
303 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
304 jumped:
305 if (!fib_rule_match(rule, ops, fl, flags, arg))
306 continue;
307
308 if (rule->action == FR_ACT_GOTO) {
309 struct fib_rule *target;
310
311 target = rcu_dereference(rule->ctarget);
312 if (target == NULL) {
313 continue;
314 } else {
315 rule = target;
316 goto jumped;
317 }
318 } else if (rule->action == FR_ACT_NOP)
319 continue;
320 else
321 err = INDIRECT_CALL_MT(ops->action,
322 fib6_rule_action,
323 fib4_rule_action,
324 rule, fl, flags, arg);
325
326 if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress,
327 fib6_rule_suppress,
328 fib4_rule_suppress,
329 rule, flags, arg))
330 continue;
331
332 if (err != -EAGAIN) {
333 if ((arg->flags & FIB_LOOKUP_NOREF) ||
334 likely(refcount_inc_not_zero(&rule->refcnt))) {
335 arg->rule = rule;
336 goto out;
337 }
338 break;
339 }
340 }
341
342 err = -ESRCH;
343 out:
344 rcu_read_unlock();
345
346 return err;
347 }
348 EXPORT_SYMBOL_GPL(fib_rules_lookup);
349
call_fib_rule_notifier(struct notifier_block * nb,enum fib_event_type event_type,struct fib_rule * rule,int family,struct netlink_ext_ack * extack)350 static int call_fib_rule_notifier(struct notifier_block *nb,
351 enum fib_event_type event_type,
352 struct fib_rule *rule, int family,
353 struct netlink_ext_ack *extack)
354 {
355 struct fib_rule_notifier_info info = {
356 .info.family = family,
357 .info.extack = extack,
358 .rule = rule,
359 };
360
361 return call_fib_notifier(nb, event_type, &info.info);
362 }
363
call_fib_rule_notifiers(struct net * net,enum fib_event_type event_type,struct fib_rule * rule,struct fib_rules_ops * ops,struct netlink_ext_ack * extack)364 static int call_fib_rule_notifiers(struct net *net,
365 enum fib_event_type event_type,
366 struct fib_rule *rule,
367 struct fib_rules_ops *ops,
368 struct netlink_ext_ack *extack)
369 {
370 struct fib_rule_notifier_info info = {
371 .info.family = ops->family,
372 .info.extack = extack,
373 .rule = rule,
374 };
375
376 ASSERT_RTNL();
377 /* Paired with READ_ONCE() in fib_rules_seq() */
378 WRITE_ONCE(ops->fib_rules_seq, ops->fib_rules_seq + 1);
379 return call_fib_notifiers(net, event_type, &info.info);
380 }
381
382 /* Called with rcu_read_lock() */
fib_rules_dump(struct net * net,struct notifier_block * nb,int family,struct netlink_ext_ack * extack)383 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
384 struct netlink_ext_ack *extack)
385 {
386 struct fib_rules_ops *ops;
387 struct fib_rule *rule;
388 int err = 0;
389
390 ops = lookup_rules_ops(net, family);
391 if (!ops)
392 return -EAFNOSUPPORT;
393 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
394 err = call_fib_rule_notifier(nb, FIB_EVENT_RULE_ADD,
395 rule, family, extack);
396 if (err)
397 break;
398 }
399 rules_ops_put(ops);
400
401 return err;
402 }
403 EXPORT_SYMBOL_GPL(fib_rules_dump);
404
fib_rules_seq_read(const struct net * net,int family)405 unsigned int fib_rules_seq_read(const struct net *net, int family)
406 {
407 unsigned int fib_rules_seq;
408 struct fib_rules_ops *ops;
409
410 ops = lookup_rules_ops(net, family);
411 if (!ops)
412 return 0;
413 /* Paired with WRITE_ONCE() in call_fib_rule_notifiers() */
414 fib_rules_seq = READ_ONCE(ops->fib_rules_seq);
415 rules_ops_put(ops);
416
417 return fib_rules_seq;
418 }
419 EXPORT_SYMBOL_GPL(fib_rules_seq_read);
420
rule_find(struct fib_rules_ops * ops,struct fib_rule_hdr * frh,struct nlattr ** tb,struct fib_rule * rule,bool user_priority)421 static struct fib_rule *rule_find(struct fib_rules_ops *ops,
422 struct fib_rule_hdr *frh,
423 struct nlattr **tb,
424 struct fib_rule *rule,
425 bool user_priority)
426 {
427 struct fib_rule *r;
428
429 list_for_each_entry(r, &ops->rules_list, list) {
430 if (rule->action && r->action != rule->action)
431 continue;
432
433 if (rule->table && r->table != rule->table)
434 continue;
435
436 if (user_priority && r->pref != rule->pref)
437 continue;
438
439 if (rule->iifname[0] &&
440 memcmp(r->iifname, rule->iifname, IFNAMSIZ))
441 continue;
442
443 if (rule->oifname[0] &&
444 memcmp(r->oifname, rule->oifname, IFNAMSIZ))
445 continue;
446
447 if (rule->mark && r->mark != rule->mark)
448 continue;
449
450 if (rule->suppress_ifgroup != -1 &&
451 r->suppress_ifgroup != rule->suppress_ifgroup)
452 continue;
453
454 if (rule->suppress_prefixlen != -1 &&
455 r->suppress_prefixlen != rule->suppress_prefixlen)
456 continue;
457
458 if (rule->mark_mask && r->mark_mask != rule->mark_mask)
459 continue;
460
461 if (rule->tun_id && r->tun_id != rule->tun_id)
462 continue;
463
464 if (r->fr_net != rule->fr_net)
465 continue;
466
467 if (rule->l3mdev && r->l3mdev != rule->l3mdev)
468 continue;
469
470 if (uid_range_set(&rule->uid_range) &&
471 (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
472 !uid_eq(r->uid_range.end, rule->uid_range.end)))
473 continue;
474
475 if (rule->ip_proto && r->ip_proto != rule->ip_proto)
476 continue;
477
478 if (rule->proto && r->proto != rule->proto)
479 continue;
480
481 if (fib_rule_port_range_set(&rule->sport_range) &&
482 !fib_rule_port_range_compare(&r->sport_range,
483 &rule->sport_range))
484 continue;
485
486 if (fib_rule_port_range_set(&rule->dport_range) &&
487 !fib_rule_port_range_compare(&r->dport_range,
488 &rule->dport_range))
489 continue;
490
491 if (!ops->compare(r, frh, tb))
492 continue;
493 return r;
494 }
495
496 return NULL;
497 }
498
499 #ifdef CONFIG_NET_L3_MASTER_DEV
fib_nl2rule_l3mdev(struct nlattr * nla,struct fib_rule * nlrule,struct netlink_ext_ack * extack)500 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
501 struct netlink_ext_ack *extack)
502 {
503 nlrule->l3mdev = nla_get_u8(nla);
504 if (nlrule->l3mdev != 1) {
505 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute");
506 return -1;
507 }
508
509 return 0;
510 }
511 #else
fib_nl2rule_l3mdev(struct nlattr * nla,struct fib_rule * nlrule,struct netlink_ext_ack * extack)512 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
513 struct netlink_ext_ack *extack)
514 {
515 NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel");
516 return -1;
517 }
518 #endif
519
fib_nl2rule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack,struct fib_rules_ops * ops,struct nlattr * tb[],struct fib_rule ** rule,bool * user_priority)520 static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
521 struct netlink_ext_ack *extack,
522 struct fib_rules_ops *ops,
523 struct nlattr *tb[],
524 struct fib_rule **rule,
525 bool *user_priority)
526 {
527 struct net *net = sock_net(skb->sk);
528 struct fib_rule_hdr *frh = nlmsg_data(nlh);
529 struct fib_rule *nlrule = NULL;
530 int err = -EINVAL;
531
532 if (frh->src_len)
533 if (!tb[FRA_SRC] ||
534 frh->src_len > (ops->addr_size * 8) ||
535 nla_len(tb[FRA_SRC]) != ops->addr_size) {
536 NL_SET_ERR_MSG(extack, "Invalid source address");
537 goto errout;
538 }
539
540 if (frh->dst_len)
541 if (!tb[FRA_DST] ||
542 frh->dst_len > (ops->addr_size * 8) ||
543 nla_len(tb[FRA_DST]) != ops->addr_size) {
544 NL_SET_ERR_MSG(extack, "Invalid dst address");
545 goto errout;
546 }
547
548 nlrule = kzalloc(ops->rule_size, GFP_KERNEL_ACCOUNT);
549 if (!nlrule) {
550 err = -ENOMEM;
551 goto errout;
552 }
553 refcount_set(&nlrule->refcnt, 1);
554 nlrule->fr_net = net;
555
556 if (tb[FRA_PRIORITY]) {
557 nlrule->pref = nla_get_u32(tb[FRA_PRIORITY]);
558 *user_priority = true;
559 } else {
560 nlrule->pref = fib_default_rule_pref(ops);
561 }
562
563 nlrule->proto = nla_get_u8_default(tb[FRA_PROTOCOL], RTPROT_UNSPEC);
564
565 if (tb[FRA_IIFNAME]) {
566 struct net_device *dev;
567
568 nlrule->iifindex = -1;
569 nla_strscpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
570 dev = __dev_get_by_name(net, nlrule->iifname);
571 if (dev)
572 nlrule->iifindex = dev->ifindex;
573 }
574
575 if (tb[FRA_OIFNAME]) {
576 struct net_device *dev;
577
578 nlrule->oifindex = -1;
579 nla_strscpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
580 dev = __dev_get_by_name(net, nlrule->oifname);
581 if (dev)
582 nlrule->oifindex = dev->ifindex;
583 }
584
585 if (tb[FRA_FWMARK]) {
586 nlrule->mark = nla_get_u32(tb[FRA_FWMARK]);
587 if (nlrule->mark)
588 /* compatibility: if the mark value is non-zero all bits
589 * are compared unless a mask is explicitly specified.
590 */
591 nlrule->mark_mask = 0xFFFFFFFF;
592 }
593
594 if (tb[FRA_FWMASK])
595 nlrule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
596
597 if (tb[FRA_TUN_ID])
598 nlrule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
599
600 if (tb[FRA_L3MDEV] &&
601 fib_nl2rule_l3mdev(tb[FRA_L3MDEV], nlrule, extack) < 0)
602 goto errout_free;
603
604 nlrule->action = frh->action;
605 nlrule->flags = frh->flags;
606 nlrule->table = frh_get_table(frh, tb);
607 if (tb[FRA_SUPPRESS_PREFIXLEN])
608 nlrule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
609 else
610 nlrule->suppress_prefixlen = -1;
611
612 if (tb[FRA_SUPPRESS_IFGROUP])
613 nlrule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
614 else
615 nlrule->suppress_ifgroup = -1;
616
617 if (tb[FRA_GOTO]) {
618 if (nlrule->action != FR_ACT_GOTO) {
619 NL_SET_ERR_MSG(extack, "Unexpected goto");
620 goto errout_free;
621 }
622
623 nlrule->target = nla_get_u32(tb[FRA_GOTO]);
624 /* Backward jumps are prohibited to avoid endless loops */
625 if (nlrule->target <= nlrule->pref) {
626 NL_SET_ERR_MSG(extack, "Backward goto not supported");
627 goto errout_free;
628 }
629 } else if (nlrule->action == FR_ACT_GOTO) {
630 NL_SET_ERR_MSG(extack, "Missing goto target for action goto");
631 goto errout_free;
632 }
633
634 if (nlrule->l3mdev && nlrule->table) {
635 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive");
636 goto errout_free;
637 }
638
639 if (tb[FRA_UID_RANGE]) {
640 if (current_user_ns() != net->user_ns) {
641 err = -EPERM;
642 NL_SET_ERR_MSG(extack, "No permission to set uid");
643 goto errout_free;
644 }
645
646 nlrule->uid_range = nla_get_kuid_range(tb);
647
648 if (!uid_range_set(&nlrule->uid_range) ||
649 !uid_lte(nlrule->uid_range.start, nlrule->uid_range.end)) {
650 NL_SET_ERR_MSG(extack, "Invalid uid range");
651 goto errout_free;
652 }
653 } else {
654 nlrule->uid_range = fib_kuid_range_unset;
655 }
656
657 if (tb[FRA_IP_PROTO])
658 nlrule->ip_proto = nla_get_u8(tb[FRA_IP_PROTO]);
659
660 if (tb[FRA_SPORT_RANGE]) {
661 err = nla_get_port_range(tb[FRA_SPORT_RANGE],
662 &nlrule->sport_range);
663 if (err) {
664 NL_SET_ERR_MSG(extack, "Invalid sport range");
665 goto errout_free;
666 }
667 }
668
669 if (tb[FRA_DPORT_RANGE]) {
670 err = nla_get_port_range(tb[FRA_DPORT_RANGE],
671 &nlrule->dport_range);
672 if (err) {
673 NL_SET_ERR_MSG(extack, "Invalid dport range");
674 goto errout_free;
675 }
676 }
677
678 *rule = nlrule;
679
680 return 0;
681
682 errout_free:
683 kfree(nlrule);
684 errout:
685 return err;
686 }
687
rule_exists(struct fib_rules_ops * ops,struct fib_rule_hdr * frh,struct nlattr ** tb,struct fib_rule * rule)688 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
689 struct nlattr **tb, struct fib_rule *rule)
690 {
691 struct fib_rule *r;
692
693 list_for_each_entry(r, &ops->rules_list, list) {
694 if (r->action != rule->action)
695 continue;
696
697 if (r->table != rule->table)
698 continue;
699
700 if (r->pref != rule->pref)
701 continue;
702
703 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
704 continue;
705
706 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
707 continue;
708
709 if (r->mark != rule->mark)
710 continue;
711
712 if (r->suppress_ifgroup != rule->suppress_ifgroup)
713 continue;
714
715 if (r->suppress_prefixlen != rule->suppress_prefixlen)
716 continue;
717
718 if (r->mark_mask != rule->mark_mask)
719 continue;
720
721 if (r->tun_id != rule->tun_id)
722 continue;
723
724 if (r->fr_net != rule->fr_net)
725 continue;
726
727 if (r->l3mdev != rule->l3mdev)
728 continue;
729
730 if (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
731 !uid_eq(r->uid_range.end, rule->uid_range.end))
732 continue;
733
734 if (r->ip_proto != rule->ip_proto)
735 continue;
736
737 if (r->proto != rule->proto)
738 continue;
739
740 if (!fib_rule_port_range_compare(&r->sport_range,
741 &rule->sport_range))
742 continue;
743
744 if (!fib_rule_port_range_compare(&r->dport_range,
745 &rule->dport_range))
746 continue;
747
748 if (!ops->compare(r, frh, tb))
749 continue;
750 return 1;
751 }
752 return 0;
753 }
754
755 static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = {
756 [FRA_UNSPEC] = { .strict_start_type = FRA_DPORT_RANGE + 1 },
757 [FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
758 [FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
759 [FRA_PRIORITY] = { .type = NLA_U32 },
760 [FRA_FWMARK] = { .type = NLA_U32 },
761 [FRA_FLOW] = { .type = NLA_U32 },
762 [FRA_TUN_ID] = { .type = NLA_U64 },
763 [FRA_FWMASK] = { .type = NLA_U32 },
764 [FRA_TABLE] = { .type = NLA_U32 },
765 [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 },
766 [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 },
767 [FRA_GOTO] = { .type = NLA_U32 },
768 [FRA_L3MDEV] = { .type = NLA_U8 },
769 [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) },
770 [FRA_PROTOCOL] = { .type = NLA_U8 },
771 [FRA_IP_PROTO] = { .type = NLA_U8 },
772 [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
773 [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) },
774 [FRA_DSCP] = NLA_POLICY_MAX(NLA_U8, INET_DSCP_MASK >> 2),
775 [FRA_FLOWLABEL] = { .type = NLA_BE32 },
776 [FRA_FLOWLABEL_MASK] = { .type = NLA_BE32 },
777 };
778
fib_nl_newrule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)779 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
780 struct netlink_ext_ack *extack)
781 {
782 struct net *net = sock_net(skb->sk);
783 struct fib_rule_hdr *frh = nlmsg_data(nlh);
784 struct fib_rules_ops *ops = NULL;
785 struct fib_rule *rule = NULL, *r, *last = NULL;
786 struct nlattr *tb[FRA_MAX + 1];
787 int err = -EINVAL, unresolved = 0;
788 bool user_priority = false;
789
790 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
791 NL_SET_ERR_MSG(extack, "Invalid msg length");
792 goto errout;
793 }
794
795 ops = lookup_rules_ops(net, frh->family);
796 if (!ops) {
797 err = -EAFNOSUPPORT;
798 NL_SET_ERR_MSG(extack, "Rule family not supported");
799 goto errout;
800 }
801
802 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
803 fib_rule_policy, extack);
804 if (err < 0) {
805 NL_SET_ERR_MSG(extack, "Error parsing msg");
806 goto errout;
807 }
808
809 err = fib_nl2rule(skb, nlh, extack, ops, tb, &rule, &user_priority);
810 if (err)
811 goto errout;
812
813 if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
814 rule_exists(ops, frh, tb, rule)) {
815 err = -EEXIST;
816 goto errout_free;
817 }
818
819 err = ops->configure(rule, skb, frh, tb, extack);
820 if (err < 0)
821 goto errout_free;
822
823 err = call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule, ops,
824 extack);
825 if (err < 0)
826 goto errout_free;
827
828 list_for_each_entry(r, &ops->rules_list, list) {
829 if (r->pref == rule->target) {
830 RCU_INIT_POINTER(rule->ctarget, r);
831 break;
832 }
833 }
834
835 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
836 unresolved = 1;
837
838 list_for_each_entry(r, &ops->rules_list, list) {
839 if (r->pref > rule->pref)
840 break;
841 last = r;
842 }
843
844 if (last)
845 list_add_rcu(&rule->list, &last->list);
846 else
847 list_add_rcu(&rule->list, &ops->rules_list);
848
849 if (ops->unresolved_rules) {
850 /*
851 * There are unresolved goto rules in the list, check if
852 * any of them are pointing to this new rule.
853 */
854 list_for_each_entry(r, &ops->rules_list, list) {
855 if (r->action == FR_ACT_GOTO &&
856 r->target == rule->pref &&
857 rtnl_dereference(r->ctarget) == NULL) {
858 rcu_assign_pointer(r->ctarget, rule);
859 if (--ops->unresolved_rules == 0)
860 break;
861 }
862 }
863 }
864
865 if (rule->action == FR_ACT_GOTO)
866 ops->nr_goto_rules++;
867
868 if (unresolved)
869 ops->unresolved_rules++;
870
871 if (rule->tun_id)
872 ip_tunnel_need_metadata();
873
874 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
875 flush_route_cache(ops);
876 rules_ops_put(ops);
877 return 0;
878
879 errout_free:
880 kfree(rule);
881 errout:
882 rules_ops_put(ops);
883 return err;
884 }
885 EXPORT_SYMBOL_GPL(fib_nl_newrule);
886
fib_nl_delrule(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)887 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
888 struct netlink_ext_ack *extack)
889 {
890 struct net *net = sock_net(skb->sk);
891 struct fib_rule_hdr *frh = nlmsg_data(nlh);
892 struct fib_rules_ops *ops = NULL;
893 struct fib_rule *rule = NULL, *r, *nlrule = NULL;
894 struct nlattr *tb[FRA_MAX+1];
895 int err = -EINVAL;
896 bool user_priority = false;
897
898 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
899 NL_SET_ERR_MSG(extack, "Invalid msg length");
900 goto errout;
901 }
902
903 ops = lookup_rules_ops(net, frh->family);
904 if (ops == NULL) {
905 err = -EAFNOSUPPORT;
906 NL_SET_ERR_MSG(extack, "Rule family not supported");
907 goto errout;
908 }
909
910 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
911 fib_rule_policy, extack);
912 if (err < 0) {
913 NL_SET_ERR_MSG(extack, "Error parsing msg");
914 goto errout;
915 }
916
917 err = fib_nl2rule(skb, nlh, extack, ops, tb, &nlrule, &user_priority);
918 if (err)
919 goto errout;
920
921 rule = rule_find(ops, frh, tb, nlrule, user_priority);
922 if (!rule) {
923 err = -ENOENT;
924 goto errout;
925 }
926
927 if (rule->flags & FIB_RULE_PERMANENT) {
928 err = -EPERM;
929 goto errout;
930 }
931
932 if (ops->delete) {
933 err = ops->delete(rule);
934 if (err)
935 goto errout;
936 }
937
938 if (rule->tun_id)
939 ip_tunnel_unneed_metadata();
940
941 list_del_rcu(&rule->list);
942
943 if (rule->action == FR_ACT_GOTO) {
944 ops->nr_goto_rules--;
945 if (rtnl_dereference(rule->ctarget) == NULL)
946 ops->unresolved_rules--;
947 }
948
949 /*
950 * Check if this rule is a target to any of them. If so,
951 * adjust to the next one with the same preference or
952 * disable them. As this operation is eventually very
953 * expensive, it is only performed if goto rules, except
954 * current if it is goto rule, have actually been added.
955 */
956 if (ops->nr_goto_rules > 0) {
957 struct fib_rule *n;
958
959 n = list_next_entry(rule, list);
960 if (&n->list == &ops->rules_list || n->pref != rule->pref)
961 n = NULL;
962 list_for_each_entry(r, &ops->rules_list, list) {
963 if (rtnl_dereference(r->ctarget) != rule)
964 continue;
965 rcu_assign_pointer(r->ctarget, n);
966 if (!n)
967 ops->unresolved_rules++;
968 }
969 }
970
971 call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule, ops,
972 NULL);
973 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
974 NETLINK_CB(skb).portid);
975 fib_rule_put(rule);
976 flush_route_cache(ops);
977 rules_ops_put(ops);
978 kfree(nlrule);
979 return 0;
980
981 errout:
982 kfree(nlrule);
983 rules_ops_put(ops);
984 return err;
985 }
986 EXPORT_SYMBOL_GPL(fib_nl_delrule);
987
fib_rule_nlmsg_size(struct fib_rules_ops * ops,struct fib_rule * rule)988 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
989 struct fib_rule *rule)
990 {
991 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
992 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
993 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
994 + nla_total_size(4) /* FRA_PRIORITY */
995 + nla_total_size(4) /* FRA_TABLE */
996 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
997 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
998 + nla_total_size(4) /* FRA_FWMARK */
999 + nla_total_size(4) /* FRA_FWMASK */
1000 + nla_total_size_64bit(8) /* FRA_TUN_ID */
1001 + nla_total_size(sizeof(struct fib_kuid_range))
1002 + nla_total_size(1) /* FRA_PROTOCOL */
1003 + nla_total_size(1) /* FRA_IP_PROTO */
1004 + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */
1005 + nla_total_size(sizeof(struct fib_rule_port_range)); /* FRA_DPORT_RANGE */
1006
1007 if (ops->nlmsg_payload)
1008 payload += ops->nlmsg_payload(rule);
1009
1010 return payload;
1011 }
1012
fib_nl_fill_rule(struct sk_buff * skb,struct fib_rule * rule,u32 pid,u32 seq,int type,int flags,struct fib_rules_ops * ops)1013 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
1014 u32 pid, u32 seq, int type, int flags,
1015 struct fib_rules_ops *ops)
1016 {
1017 struct nlmsghdr *nlh;
1018 struct fib_rule_hdr *frh;
1019
1020 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
1021 if (nlh == NULL)
1022 return -EMSGSIZE;
1023
1024 frh = nlmsg_data(nlh);
1025 frh->family = ops->family;
1026 frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT;
1027 if (nla_put_u32(skb, FRA_TABLE, rule->table))
1028 goto nla_put_failure;
1029 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
1030 goto nla_put_failure;
1031 frh->res1 = 0;
1032 frh->res2 = 0;
1033 frh->action = rule->action;
1034 frh->flags = rule->flags;
1035
1036 if (nla_put_u8(skb, FRA_PROTOCOL, rule->proto))
1037 goto nla_put_failure;
1038
1039 if (rule->action == FR_ACT_GOTO &&
1040 rcu_access_pointer(rule->ctarget) == NULL)
1041 frh->flags |= FIB_RULE_UNRESOLVED;
1042
1043 if (rule->iifname[0]) {
1044 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
1045 goto nla_put_failure;
1046 if (READ_ONCE(rule->iifindex) == -1)
1047 frh->flags |= FIB_RULE_IIF_DETACHED;
1048 }
1049
1050 if (rule->oifname[0]) {
1051 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
1052 goto nla_put_failure;
1053 if (READ_ONCE(rule->oifindex) == -1)
1054 frh->flags |= FIB_RULE_OIF_DETACHED;
1055 }
1056
1057 if ((rule->pref &&
1058 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
1059 (rule->mark &&
1060 nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
1061 ((rule->mark_mask || rule->mark) &&
1062 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
1063 (rule->target &&
1064 nla_put_u32(skb, FRA_GOTO, rule->target)) ||
1065 (rule->tun_id &&
1066 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
1067 (rule->l3mdev &&
1068 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
1069 (uid_range_set(&rule->uid_range) &&
1070 nla_put_uid_range(skb, &rule->uid_range)) ||
1071 (fib_rule_port_range_set(&rule->sport_range) &&
1072 nla_put_port_range(skb, FRA_SPORT_RANGE, &rule->sport_range)) ||
1073 (fib_rule_port_range_set(&rule->dport_range) &&
1074 nla_put_port_range(skb, FRA_DPORT_RANGE, &rule->dport_range)) ||
1075 (rule->ip_proto && nla_put_u8(skb, FRA_IP_PROTO, rule->ip_proto)))
1076 goto nla_put_failure;
1077
1078 if (rule->suppress_ifgroup != -1) {
1079 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
1080 goto nla_put_failure;
1081 }
1082
1083 if (ops->fill(rule, skb, frh) < 0)
1084 goto nla_put_failure;
1085
1086 nlmsg_end(skb, nlh);
1087 return 0;
1088
1089 nla_put_failure:
1090 nlmsg_cancel(skb, nlh);
1091 return -EMSGSIZE;
1092 }
1093
dump_rules(struct sk_buff * skb,struct netlink_callback * cb,struct fib_rules_ops * ops)1094 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
1095 struct fib_rules_ops *ops)
1096 {
1097 int idx = 0;
1098 struct fib_rule *rule;
1099 int err = 0;
1100
1101 rcu_read_lock();
1102 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
1103 if (idx < cb->args[1])
1104 goto skip;
1105
1106 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
1107 cb->nlh->nlmsg_seq, RTM_NEWRULE,
1108 NLM_F_MULTI, ops);
1109 if (err)
1110 break;
1111 skip:
1112 idx++;
1113 }
1114 rcu_read_unlock();
1115 cb->args[1] = idx;
1116 rules_ops_put(ops);
1117
1118 return err;
1119 }
1120
fib_valid_dumprule_req(const struct nlmsghdr * nlh,struct netlink_ext_ack * extack)1121 static int fib_valid_dumprule_req(const struct nlmsghdr *nlh,
1122 struct netlink_ext_ack *extack)
1123 {
1124 struct fib_rule_hdr *frh;
1125
1126 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
1127 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request");
1128 return -EINVAL;
1129 }
1130
1131 frh = nlmsg_data(nlh);
1132 if (frh->dst_len || frh->src_len || frh->tos || frh->table ||
1133 frh->res1 || frh->res2 || frh->action || frh->flags) {
1134 NL_SET_ERR_MSG(extack,
1135 "Invalid values in header for fib rule dump request");
1136 return -EINVAL;
1137 }
1138
1139 if (nlmsg_attrlen(nlh, sizeof(*frh))) {
1140 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request");
1141 return -EINVAL;
1142 }
1143
1144 return 0;
1145 }
1146
fib_nl_dumprule(struct sk_buff * skb,struct netlink_callback * cb)1147 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
1148 {
1149 const struct nlmsghdr *nlh = cb->nlh;
1150 struct net *net = sock_net(skb->sk);
1151 struct fib_rules_ops *ops;
1152 int err, idx = 0, family;
1153
1154 if (cb->strict_check) {
1155 err = fib_valid_dumprule_req(nlh, cb->extack);
1156
1157 if (err < 0)
1158 return err;
1159 }
1160
1161 family = rtnl_msg_family(nlh);
1162 if (family != AF_UNSPEC) {
1163 /* Protocol specific dump request */
1164 ops = lookup_rules_ops(net, family);
1165 if (ops == NULL)
1166 return -EAFNOSUPPORT;
1167
1168 return dump_rules(skb, cb, ops);
1169 }
1170
1171 err = 0;
1172 rcu_read_lock();
1173 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
1174 if (idx < cb->args[0] || !try_module_get(ops->owner))
1175 goto skip;
1176
1177 err = dump_rules(skb, cb, ops);
1178 if (err < 0)
1179 break;
1180
1181 cb->args[1] = 0;
1182 skip:
1183 idx++;
1184 }
1185 rcu_read_unlock();
1186 cb->args[0] = idx;
1187
1188 return err;
1189 }
1190
notify_rule_change(int event,struct fib_rule * rule,struct fib_rules_ops * ops,struct nlmsghdr * nlh,u32 pid)1191 static void notify_rule_change(int event, struct fib_rule *rule,
1192 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
1193 u32 pid)
1194 {
1195 struct net *net;
1196 struct sk_buff *skb;
1197 int err = -ENOMEM;
1198
1199 net = ops->fro_net;
1200 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
1201 if (skb == NULL)
1202 goto errout;
1203
1204 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
1205 if (err < 0) {
1206 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
1207 WARN_ON(err == -EMSGSIZE);
1208 kfree_skb(skb);
1209 goto errout;
1210 }
1211
1212 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
1213 return;
1214 errout:
1215 rtnl_set_sk_err(net, ops->nlgroup, err);
1216 }
1217
attach_rules(struct list_head * rules,struct net_device * dev)1218 static void attach_rules(struct list_head *rules, struct net_device *dev)
1219 {
1220 struct fib_rule *rule;
1221
1222 list_for_each_entry(rule, rules, list) {
1223 if (rule->iifindex == -1 &&
1224 strcmp(dev->name, rule->iifname) == 0)
1225 WRITE_ONCE(rule->iifindex, dev->ifindex);
1226 if (rule->oifindex == -1 &&
1227 strcmp(dev->name, rule->oifname) == 0)
1228 WRITE_ONCE(rule->oifindex, dev->ifindex);
1229 }
1230 }
1231
detach_rules(struct list_head * rules,struct net_device * dev)1232 static void detach_rules(struct list_head *rules, struct net_device *dev)
1233 {
1234 struct fib_rule *rule;
1235
1236 list_for_each_entry(rule, rules, list) {
1237 if (rule->iifindex == dev->ifindex)
1238 WRITE_ONCE(rule->iifindex, -1);
1239 if (rule->oifindex == dev->ifindex)
1240 WRITE_ONCE(rule->oifindex, -1);
1241 }
1242 }
1243
1244
fib_rules_event(struct notifier_block * this,unsigned long event,void * ptr)1245 static int fib_rules_event(struct notifier_block *this, unsigned long event,
1246 void *ptr)
1247 {
1248 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1249 struct net *net = dev_net(dev);
1250 struct fib_rules_ops *ops;
1251
1252 ASSERT_RTNL();
1253
1254 switch (event) {
1255 case NETDEV_REGISTER:
1256 list_for_each_entry(ops, &net->rules_ops, list)
1257 attach_rules(&ops->rules_list, dev);
1258 break;
1259
1260 case NETDEV_CHANGENAME:
1261 list_for_each_entry(ops, &net->rules_ops, list) {
1262 detach_rules(&ops->rules_list, dev);
1263 attach_rules(&ops->rules_list, dev);
1264 }
1265 break;
1266
1267 case NETDEV_UNREGISTER:
1268 list_for_each_entry(ops, &net->rules_ops, list)
1269 detach_rules(&ops->rules_list, dev);
1270 break;
1271 }
1272
1273 return NOTIFY_DONE;
1274 }
1275
1276 static struct notifier_block fib_rules_notifier = {
1277 .notifier_call = fib_rules_event,
1278 };
1279
fib_rules_net_init(struct net * net)1280 static int __net_init fib_rules_net_init(struct net *net)
1281 {
1282 INIT_LIST_HEAD(&net->rules_ops);
1283 spin_lock_init(&net->rules_mod_lock);
1284 return 0;
1285 }
1286
fib_rules_net_exit(struct net * net)1287 static void __net_exit fib_rules_net_exit(struct net *net)
1288 {
1289 WARN_ON_ONCE(!list_empty(&net->rules_ops));
1290 }
1291
1292 static struct pernet_operations fib_rules_net_ops = {
1293 .init = fib_rules_net_init,
1294 .exit = fib_rules_net_exit,
1295 };
1296
1297 static const struct rtnl_msg_handler fib_rules_rtnl_msg_handlers[] __initconst = {
1298 {.msgtype = RTM_NEWRULE, .doit = fib_nl_newrule},
1299 {.msgtype = RTM_DELRULE, .doit = fib_nl_delrule},
1300 {.msgtype = RTM_GETRULE, .dumpit = fib_nl_dumprule,
1301 .flags = RTNL_FLAG_DUMP_UNLOCKED},
1302 };
1303
fib_rules_init(void)1304 static int __init fib_rules_init(void)
1305 {
1306 int err;
1307
1308 rtnl_register_many(fib_rules_rtnl_msg_handlers);
1309
1310 err = register_pernet_subsys(&fib_rules_net_ops);
1311 if (err < 0)
1312 goto fail;
1313
1314 err = register_netdevice_notifier(&fib_rules_notifier);
1315 if (err < 0)
1316 goto fail_unregister;
1317
1318 return 0;
1319
1320 fail_unregister:
1321 unregister_pernet_subsys(&fib_rules_net_ops);
1322 fail:
1323 rtnl_unregister_many(fib_rules_rtnl_msg_handlers);
1324 return err;
1325 }
1326
1327 subsys_initcall(fib_rules_init);
1328